Magnetic reconnection at a thin current sheet separating two interlaced flux tubes at the Earth's magnetopause
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
The occurrence of spatially and temporally variable reconnection at the Earth's magnetopause leads to the complex interaction of magnetic fields from the magnetosphere and magnetosheath. Flux transfer events (FTEs) constitute one such type of interaction. Their main characteristics are (1) an enhanced core magnetic field magnitude and (2) a bipolar magnetic field signature in the component normal to the magnetopause, reminiscent of a large-scale helicoidal flux tube magnetic configuration. However, other geometrical configurations which do not fit this classical picture have also been observed. Using high-resolution measurements from the Magnetospheric Multiscale mission, we investigate an event in the vicinity of the Earth's magnetopause on 7 November 2015. Despite signatures that, at first glance, appear consistent with a classic FTE, based on detailed geometrical and dynamical analyses as well as on topological signatures revealed by suprathermal electron properties, we demonstrate that this event is not consistent with a single, homogenous helicoidal structure. Our analysis rather suggests that it consists of the interaction of two separate sets of magnetic field lines with different connectivities. This complex three-dimensional interaction constructively conspires to produce signatures partially consistent with that of an FTE. We also show that, at the interface between the two sets of field lines, where the observed magnetic pileup occurs, a thin and strong current sheet forms with a large ion jet, which may be consistent with magnetic flux dissipation through magnetic reconnection in the interaction region.
Date Issued
2018-03-06
Date Acceptance
2018-01-27
Citation
Journal of Geophysical Research: Space Physics, 2018, 123 (3), pp.1779-1793
ISSN
2169-9380
Publisher
American Geophysical Union
Start Page
1779
End Page
1793
Journal / Book Title
Journal of Geophysical Research: Space Physics
Volume
123
Issue
3
Copyright Statement
© 2018. American Geophysical Union. All Rights Reserved. An edited version of this paper was published by AGU. To view the published open abstract, go to: https://dx.doi.org/10.1002/2017JA024537
Sponsor
Science and Technology Facilities Council (STFC)
Grant Number
ST/N000692/1
Subjects
Science & Technology
Physical Sciences
Astronomy & Astrophysics
MAGNETOSPHERIC MULTISCALE MISSION
TRANSFER EVENTS
CLUSTER OBSERVATIONS
ELECTRON ACCELERATION
DAYSIDE MAGNETOPAUSE
COORDINATED CLUSTER
LINE RECONNECTION
GUIDE FIELD
PLASMA
SPACECRAFT
Publication Status
Published
Date Publish Online
2018-02-20